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排序方式: 共有870条查询结果,搜索用时 15 毫秒
1.
Maria A Hortis-Dzierzbicka Zofia Dudkiewicz 《The Cleft palate-craniofacial journal》2004,41(1):105; author reply 105-105; author reply 106
2.
Brian K Owler Shahan Momjian Zofia Czosnyka Marek Czosnyka Alonso Péna Neil G Harris Piotr Smielewski Tim Fryer Tim Donovan Jonathon Coles Adrian Carpenter John D Pickard 《Journal of cerebral blood flow and metabolism》2004,24(1):17-23
Regional cerebral blood flow (CBF) was studied with O(15)-water positron emission tomography and anatomic region-of-interest analysis on co-registered magnetic resonance in patients with idiopathic (n = 12) and secondary (n = 5) normal pressure hydrocephalus (NPH). Mean CBF was compared with values obtained from healthy volunteers (n = 12) and with clinical parameters. Mean CBF was significantly decreased in the cerebrum and cerebellum of patients with NPH. The regional analysis demonstrated that CBF was reduced in the basal ganglia and the thalamus but not in white matter regions. The results suggest that the role of the basal ganglia and thalamus in NPH may be more prominent than currently appreciated. The implications for theories regarding the pathogenesis of NPH are discussed. 相似文献
3.
Piotrowski WJ Marczak J Kurmanowska Z Górski P 《Archivum immunologiae et therapiae experimentalis》2004,52(6):435-440
INTRODUCTION: Oxidative lung damage may be associated with the destruction of alveolar cells. Type II alveolar epithelial cells (AECs),as progenitors of type I cells, are indispensable for the renovation of alveolar structure after lung injury. Extensive damage to type II cells could be responsible for unfavorable outcome. However, the susceptibility of type II AECs to oxidative stress is unclear. MATERIAL/METHODS: We investigated the susceptibility of freshly isolated and cultured rat type II AECs to oxidative stress (H2O2 and Fe2+). Thiobarbituric acid reactive substances (TBARS)were measured as indices of lipid peroxidation and cytotoxicity was estimated by the MTT test. Aminotriazol (ATZ), an inhibitor of intracellular catalase, was used to estimate the protective role of catalase. RESULTS: TBARS concentration increased significantly in freshly isolated, oxidant-exposed cells (4.0 +/-1.3 vs.8.3 +/-2.2 nmol/g protein, p=0.0313)and insignificantly in cultured cells (1.7 +/-0.4 vs.4.4 +/-1.7 nmol/g protein).ATZ was toxic even to cells not exposed to oxidants. Inhibition of catalase in cells exposed to oxidants resulted in an insignificant increase in TBARs:4.5 +/-1.5 vs.16.2 +/-3.9 nmol/g protein, p=0.0625,and 4.0 +/-0.8 vs.7.6 +/-4.0 for freshly isolated and cultured cells, respectively. Oxidative stress itself did not increase cytotoxicity. CONCLUSIONS: Type II AECs are not resistant to oxidative stress. We cannot, however, explain why cells with evidence of lipid peroxidation do not show increased cytotoxicity. The toxicity of ATZ is not related to oxidative cell damage. In cells exposed to oxidants, TBARS may fur-ther increase when catalase is inhibited, which suggests an important protective role for catalase. 相似文献
4.
Cytomegalovirus Isolation from a Chimpanzee with Acute Demyelinating Disease After Inoculation of Multiple Sclerosis Brain Cells 下载免费PDF全文
Zofia Wroblewska Donald Gilden Mary Devlin Eng-Shang Huang Lucy B. Rorke Takeshi Hamada Toru Furukawa Larry Cummins Seymour Kalter Hilary Koprowski 《Infection and immunity》1979,25(3):1008-1015
A strain of cytomegalovirus (CMV) was isolated during the third subcultivation of explants from the left frontal lobe of a chimpanzee that developed paralysis more than 3 years after intracerebral inoculation at birth with brain cell cultures derived from a patient with multiple sclerosis. Another strain of CMV was also isolated from a lymph node culture taken from the same chimp. The isolates, designated MZM-13 and MZM-14, produced a cytopathic effect characteristic for CMV when inoculated into brain, ganglion, or fibroblast cultures of human or simian origin. Infected cells contained characteristic Cowdry A intranuclear as well as intracytoplasmic inclusion bodies, and 100-nm spherical herpes-like virus particles were detected by electron microscopy in the nucleus and cytoplasm of infected cells. Virus was further identified as CMV with convalescent human anti-CMV serum. Complement-fixing antibody to CMV was present at a titer of 1:32 when the acutely ill chimpanzee was sacrificed. No antibody was detected at birth or at 1 or 2 years of age. A newborn chimpanzee inoculated intracerebrally with MZM-13 developed clinically asymptomatic lesions in the central nervous system characterized by acute and chronic inflammation and degeneration of myelin in cranial and spinal nerve roots. Restriction endonuclease analysis of viral deoxyribonucleic acid isolated from these two viruses indicated that MZM-13 and MZM-14 are identical and are closely related to chimpanzee CMV. No similarity in restriction endonuclease fragment patterns was found between MZM virus and the Towne and Clegg strains of human CMV. 相似文献
5.
Franciszek Burdan Zofia Siezieniewska Ryszard Maciejewski Barbara Madej Elzbieta Radzikowska Zbigniew Wojtowicz 《Experimental and toxicologic pathology》2002,53(6):453-459
The aim of the study was to establish the influence of short-time omeprazole administration on liver function and morphology. Omeprazole was administered intraperitoneally, twice daily, for 3 days to male Wistar rats in two doses: 0.571 mg/kg and 5.71 mg/kg. Control animals were treated with physiological saline. Half of the animals were sacrificed 12 hours after the last injection. The remaining rats were raised for another 6 weeks, without any xenobiotics, and sacrificed on the 47th day of the experiment. The activity of free and bound fractions of hepatic acid phosphatase, beta-galactosidase, beta-N-acetyl-glucosaminidase, cathepsin B, D and L, lipase, and sulphatase were determined spectrophotometrically in homogenates of the liver. The liver sections were examined by light microscopy with hematoxylin-eosin, azan, and periodic acid-Schiff stains. Marginally significant (p < 0.1) differences in activity of free sulphatase fraction, and free and bound fractions of beta-galactosidase were found in animals exposed to the higher dose of omeprazole and sacrificed 12 hours after the last injection. Enzymatic profiles were normalised during the next 6 weeks. Histological evaluation revealed small degenerative and adaptive changes in all examined groups. It could be concluded that observed differences of hepatic lysosomal enzyme activities were the result of accompanied chemical-induced peritonitis as previously reported, and not a direct drug-toxic effect. 相似文献
6.
We have studied the influence of a temperature-sensitive cdc2-1 mutation in DNA polymerase on the selection-induced mutation occurring at the LYS-2 locus in the yeast Saccharomyces cerevisiae. It was found that in cells plated on synthetic complete medium lacking only lysine, the numbers of Lys+ revertant colonies accumulated in a time-dependent manner in the absence of any detectable increase in cell number. When cdc2-1 mutant cells, after selective plating, were incubated at the restrictive temperature of 37°C for 5 h daily for 7 days, the frequency of an adaptive reversion of lys
- Lys+ was significantly higher than the frequency in cells incubated only at the permissive temperature, or in wild-type cells incubated either at 23°C or 37°C. Therefore, when the proof-reading activity of DNA polymerase is impaired under restrictive conditions, the frequency of adaptive mutations is markedly enhanced. 相似文献
7.
The researched has dealt with the type of acetylation in 237 TB patients treated with standard course of chemotherapy with a dose of 300 mg of INH in period 1990-1997 in National Research Institute of Tuberculosis and Lung Disease in Warsaw Blood samples were taken before (time 0) and 1, 3, 6 and 24 h after drug administration. Plasma concentrations of isoniazid were determined with biological methods. Two indies of acetylation rate--I3 and C6 have been used to determine an acetylation type. Majority of the treated patients (68.8%) have shown fast type of INH acetylation. After similar dose of isoniazid different profile of absorption and excretion of the drug and significant differences (p < 0.01) in INH concentrations, acetylation rate and bioavailability between 163 fast and 74 slow acetylators have been observed. In plasma of 38.6% fast acetylators drug concentration 3 h after ingestion of a dose did not achieve the concentration of 1 mcg/ml. In plasma of 29.7% slow acetylators, concentrations of INH 6 h after ingestion were higher than 2 mcg/ml. 相似文献
8.
9.
P-glycoprotein expression influences the result of 99mTc-MIBI scintigraphy in tertiary hyperparathyroidism 总被引:2,自引:0,他引:2
Chudzinski W Niderla J Lasiecka Z Wilczynski G Gornicka B Wasiutynski A Maczewska J Kobylecka M Krolicki L Durlik M Nowacka E Lazarczyk M Dziunycz P Milewski L Nawrot I Grzela T 《International journal of molecular medicine》2005,16(2):215-219
Precise localization of parathyroid glands using 99mTc-labeled hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) scintigraphy could be affected by various biological factors. There is increasing evidence that radiotracer retention could be controlled by members of multidrug resistance (MDR) system, especially P-glycoprotein (P-gp). Since the role of P-gp in tertiary hyperparathyroidism (T-HPTH) scintigraphic studies is poorly recognized, the aim of the study was to compare the correlation between parathyroid P-gp expression and results of their scintigraphy in T-HPTH versus primary hyperparathyroidism (P-HPTH). P-HPTH (n = 19) and T-HPTH (n = 18) patients were subjected to 99mTc-MIBI scintigraphy followed by surgical treatment. The parathyroid glands were assessed in routine hematoxylin-eosin staining and P-gp expression was analyzed using immunohistochemistry. Parathyroids collected during cadaver donor multi-organ harvesting were used as a control. It has been found that P-HPTH-derived parathyroid glands with predominating adenoma morphology expressed less P-gp, as compared to P-gp-rich T-HPTH glands, mainly displaying nodular or diffused hyperplasia phenotype. This finding reversely correlated with results of 99mTc-MIBI scintigraphy. However, we did not observe any difference in P-gp expression nor scintigraphy result between nodular or diffused hyperplasia. Altogether, these data suggest that P-gp overexpression in T-HPTH could be responsible for decreased sensitivity of 99mTc-MIBI scintigraphy in those patients. Therefore, the recently proposed reduced neck exploration or limited parathyroid resection on the basis of scintigraphy could create the risk of persisted/recurrent hyperparathyroidism. However, this problem requires further study. 相似文献
10.
Zofia Szczuka Ewa Kulis Monika Boberska Anna Banik Maria Siwa Hanna Zaleskiewicz Nina Knoll Tracey A. Revenson Aleksandra Luszczynska 《British journal of health psychology》2023,28(2):451-466